CVE-2026-59781
Improper validation of custom installation directories on Windows could allow installation into locations with unsafe permissions, increasing the risk of DLL sideloading.
When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios.
Attack profile
How easy it is to exploit
- Attack vector
- Local
- Complexity
- Low
- Privileges needed
- Low
- User interaction
- Passive
What an attacker can affect
- Confidentiality
- High
- Integrity
- High
- Availability
- High
Exploit likelihood
What each source reports
CVE List Score used
5.4
Improper validation of custom installation directories on Windows could allow installation into locations with unsafe permissions, increasing the risk of DLL sideloading.
When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios.
- Record
CVE-2026-59781- CVSS 4.0
- 5.4 Medium
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Weakness
- CWE-427
- Updated
- 2026-11-02
EUVDEUVD-2026-60742
5.4
When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios.
- Record
EUVD-2026-60742- CVSS 4.0
- 5.4 Medium
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - Updated
- 2026-11-02
GitHub AdvisoriesGHSA-734c-5898-qrph
5.4
When Zabbix Agent was installed on Windows into a custom installation directory, the installer...
When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios.
- Record
GHSA-734c-5898-qrph- CVSS 4.0
- 5.4 Medium
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-427
- Updated
- 2026-11-02
NVD
5.4
When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios.
- Record
CVE-2026-59781- CVSS 4.0
- 5.4 Medium
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N/E:X/CR:X/IR:X/AR:X/MAV:X/MAC:X/MAT:X/MPR:X/MUI:X/MVC:X/MVI:X/MVA:X/MSC:X/MSI:X/MSA:X/S:X/AU:X/R:X/V:X/RE:X/U:X - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Weakness
- CWE-427
- Updated
- 2026-11-02
OSV
7.8
When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios.
- Record
CVE-2026-59781- CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
OSVUBUNTU-CVE-2026-59781
5.4
When Zabbix Agent was installed on Windows into a custom installation directory, the installer did not verify whether the selected directory had secure access permissions. If the target directory allowed unauthorized users to modify its contents, an attacker could place a malicious DLL that could later be loaded by the application, resulting in DLL sideloading. The installer has been hardened to detect potentially unsafe installation directories and now requires explicit user confirmation before proceeding with installation in such locations. This reduces the risk of accidental installation into directories with inappropriate permissions while preserving compatibility with existing deployment scenarios.
- Record
UBUNTU-CVE-2026-59781- CVSS 4.0
- 5.4 Medium
CVSS:4.0/AV:L/AC:L/AT:P/PR:L/UI:P/VC:H/VI:H/VA:H/SC:N/SI:N/SA:N - CVSS 3.1
- 7.8 High
CVSS:3.1/AV:L/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H - Updated
- 2026-11-02
Affected products
Affected packages
| Package | Affected | Fixed |
|---|---|---|
zabbixUbuntu:Pro:14.04:LTS |
All versions, plus listed versions 1:2.0.6+dfsg-1ubuntu21:2.2.0+dfsg-1ubuntu11:2.2.0+dfsg-6ubuntu11:2.2.1+dfsg-1ubuntu31:2.2.2+dfsg-1ubuntu1 Show 4 moreShow less1:2.2.2+dfsg-1ubuntu1+esm11:2.2.2+dfsg-1ubuntu1+esm31:2.2.2+dfsg-1ubuntu1+esm41:2.2.2+dfsg-1ubuntu1+esm5 |
None known |
zabbixUbuntu:Pro:16.04:LTS |
All versions, plus listed versions 1:2.4.6+dfsg-11:2.4.7+dfsg-11:2.4.7+dfsg-21:2.4.7+dfsg-2ubuntu21:2.4.7+dfsg-2ubuntu2.1 Show 4 moreShow less1:2.4.7+dfsg-2ubuntu2.1+esm11:2.4.7+dfsg-2ubuntu2.1+esm21:2.4.7+dfsg-2ubuntu2.1+esm31:2.4.7+dfsg-2ubuntu2.1+esm4 |
None known |
zabbixUbuntu:Pro:18.04:LTS |
All versions, plus listed versions 1:3.0.7+dfsg-31:3.0.12+dfsg-11:3.0.12+dfsg-1ubuntu0.1~esm11:3.0.12+dfsg-1ubuntu0.1~esm21:3.0.12+dfsg-1ubuntu0.1~esm31:3.0.12+dfsg-1ubuntu0.1~esm4 |
None known |
zabbixUbuntu:Pro:20.04:LTS |
All versions, plus listed versions 1:4.0.4+dfsg-1build21:4.0.4+dfsg-1build31:4.0.11+dfsg-11:4.0.14+dfsg-11:4.0.15+dfsg-1 Show 5 moreShow less1:4.0.16+dfsg-11:4.0.16+dfsg-1build11:4.0.17+dfsg-11:4.0.17+dfsg-1ubuntu0.1~esm11:4.0.17+dfsg-1ubuntu0.1~esm2 |
None known |
zabbixUbuntu:Pro:22.04:LTS |
All versions, plus listed versions 1:5.0.8+dfsg-1build11:5.0.14+dfsg-11:5.0.17+dfsg-11:5.0.17+dfsg-1ubuntu0.1~esm1 |
None known |
zabbixUbuntu:26.10 |
All versions, plus listed versions 1:7.0.22+dfsg-11:7.0.22+dfsg-1.11:7.0.22+dfsg-1.1build11:7.0.22+dfsg-1.1build21:7.0.27+dfsg-1 |
None known |
zabbixUbuntu:26.04:LTS |
All versions, plus listed versions 1:7.0.10+dfsg-2build11:7.0.22+dfsg-1 |
None known |
History
| Recorded | Changed | Sources |
|---|---|---|
| first indexed | CVE List, EUVD, GitHub Advisories, NVD, OSV |
Dates are when Every CVE recorded each change. Upstream dates may differ.
In short
CVE-2026-59781 is a medium vulnerability (CVSS 5.4) in Zabbix, published August 18, 2026. No source lists public exploit code. EPSS puts the chance of exploitation in the next 30 days at 0.16%, the 4th percentile. No source names a fixed version.